Cartilage trimmers and associated methods

ABSTRACT

A cartilage trimmer according to an exemplary aspect of the present disclosure includes, inter alia, a guide pin connected to a cutter with a blade projecting from only one side of the guide pin.

RELATED APPLICATION(S)

This disclosure is a continuation of prior U.S. application Ser. No.15/017,963, filed Feb. 8, 2016, the entirety of which is hereinincorporated by reference.

BACKGROUND

This disclosure relates to cartilage trimmers for use during a surgicalprocedure. Cartilage trimmers can be used to resect or remove damagedcartilage. In one example procedure, a cartilage trimmer can removedamaged cartilage on an articular surface, and then graft material canreplace the defect. The remaining, undamaged cartilage establishes astable border for the graft material.

SUMMARY

This disclosure relates to a cartilage trimmer and associated methods.In an example, a disclosed cartilage trimmer can be assembled duringsurgery by inserting a guide pin into a joint space and connecting acutter, which is deployed arthroscopically, to the guide pin. In anotherexample, the cutter is selectively moveable relative to the guide pinand deployed via an opening adjacent an end of the guide pin. In anexample, a disclosed cartilage trimmer can be used to resect cartilagein relatively narrow joint spaces. In an embodiment, the cartilage isarticular cartilage.

A cartilage trimmer according to an exemplary aspect of the presentdisclosure includes, inter alia, a guide pin connected to a cutter witha blade projecting from only one side of the guide pin.

In a further non-limiting embodiment, an angular position of the bladeis adjustable relative to the guide pin.

In a further non-limiting embodiment, the angular position of the bladeis adjustable relative to a normal to a longitudinal axis of the guidepin by about 20 to about 30 degrees in a distal direction and by about20 to about 30 degrees in a proximal direction.

In a further non-limiting embodiment, the guide pin includes a firstconnection portion adjacent a distal end thereof, the cutter includes asecond connection portion, and the first and second connection portionsare connectable.

In a further non-limiting embodiment, the first connection portionincludes an opening in a side of the guide pin, and the secondconnection portion is received in the opening.

In a further non-limiting embodiment, the connection between the firstand second connection portions is threaded.

In a further non-limiting embodiment, a bushing is received in theopening, and the bushing is moveable relative to the opening to adjustan angle of the cutter relative to the guide pin.

In a further non-limiting embodiment, the second connection portionincludes a slot, and the first connection portion includes a retentionpin selectively moveable into the slot.

In a further non-limiting embodiment, the first connection portionincludes threads about an exterior of the guide pin, and the secondconnection portion comprises a threaded bushing configured to bethreadably engaged with the threads of the guide pin.

In a further non-limiting embodiment, the cutter includes a socket, andthe threaded bushing is received in the socket. The socket is moveablerelative to the threaded bushing to adjust an angle of the cutterrelative to the guide pin.

A cartilage trimmer according to another exemplary aspect of the presentdisclosure includes, inter alia, a guide pin and a cutter. The cutterincludes a blade moveable between a retracted position within the guidepin and a deployed position projecting from the guide pin. Further, theblade has a cutting surface only on a proximal edge of the blade.

In a further non-limiting embodiment, the cutter further comprises a) arod moveable within the guide pin, and b) the blade at a distal end.

In a further non-limiting embodiment, the guide pin includes an internalpassageway and an opening adjacent a distal end thereof. Further, theblade projects through the opening when in the deployed position.

In a further non-limiting embodiment, the opening is in a side of theguide pin, and the internal passageway includes an angled wall adjacentthe opening to facilitate movement of the blade between the retractedposition and the deployed position.

In a further non-limiting embodiment, the blade is moveable between afolded position substantially parallel to the rod and a cutting positionsubstantially normal to the rod. The blade can also be biased to thecutting position.

In a further non-limiting embodiment, the opening is at a distal end ofthe guide pin.

A method of using a cartilage trimmer according to an exemplary aspectof the present disclosure includes connecting the cutter to a guide pinin a joint space. The cutter comprises a blade projecting from only oneside of the guide pin.

In a further non-limiting embodiment, a method includes resectingcartilage with the blade.

In a further non-limiting embodiment, the cartilage is articularcartilage.

In a further non-limiting embodiment, the method includes adjusting anangle of the blade relative to the guide pin while resecting cartilage.

The embodiments, examples and alternatives of the preceding paragraphs,the claims, or the following description and drawings, including any oftheir various aspects or respective individual features, may be takenindependently or in any combination. Features described in connectionwith one embodiment are applicable to all embodiments, unless suchfeatures are incompatible.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings can be briefly described as follows:

FIG. 1 illustrates a first example cartilage trimmer relative to a kneejoint. In FIG. 1, the cartilage trimmer is unassembled.

FIG. 2 illustrates the first example cartilage trimmer relative to theknee joint. In FIG. 2, the cartilage trimmer is assembled.

FIG. 3 is a cross-sectional view of the first example cartilage trimmer.

FIG. 4 is a close-up view of the encircled area in FIG. 3.

FIG. 5 is a cross-sectional view of a second example cartilage trimmer.

FIG. 6 is an exploded view of a third example cartilage trimmer.

FIG. 7 is an exploded view of a bushing, socket, and plate associatedwith the third example cartilage trimmer.

FIG. 8 is a cross-sectional view of the bushing, socket, and plateassociated with the third example cartilage trimmer.

FIG. 9 is a cross-sectional view of a fourth example cartilage trimmer.

FIG. 10 is a cross-sectional view of a fifth example cartilage trimmer.

DETAILED DESCRIPTION

This disclosure relates to a cartilage trimmer and associated methods.In an example, a disclosed cartilage trimmer can be assembled duringsurgery by inserting a guide pin into a joint space and connecting acutter, which is deployed arthroscopically, to the guide pin. In anotherexample, the cutter is selectively moveable relative to the guide pinand deployed via an opening adjacent an end of the guide pin. In anexample, a disclosed cartilage trimmer can be used to resect cartilagein relatively narrow joint spaces. In an embodiment, the cartilage isarticular cartilage.

FIGS. 1-2 illustrate an example cartilage trimmer 20, which includes aguide pin 22 and a cutter 24, relative to a joint space 26. In thisexample, the joint space 26 is a joint cavity in a knee, and isspecifically a cavity between a femur 28 and a tibia 30. While a kneejoint is illustrated, this disclosure extends to cartilage trimmers forother joints.

The cartilage trimmer 20 is configured to resect torn or damagedcartilage in the joint space 26. In this example, the cartilage trimmer20 is used to resect a tear 32 in a meniscus 34. The cartilage trimmer20 can be used to resect other cartilage structures, including articularcartilage.

As generally mentioned above, the cartilage trimmer 20 is configured tobe assembled during surgery. In the example of FIGS. 1-2, the cartilagetrimmer 20 is assembled by first inserting the guide pin 22 into thejoint space 26. In this example, the guide pin 22 is inserted into thejoint space 26 by way of a tunnel 36 formed in the tibia 30. Once theguide pin 22 is positioned in the joint space 26, the cutter 24 isdeployed arthroscopically, as generally shown in FIG. 1, and connectedto the guide pin 22 by a tool 38 such as a grasper, as generally shownin FIG. 2. The assembled cartilage trimmer 20 is then used to resect thetear 32. Because cartilage is relatively soft, a surgeon typicallymaneuvers the guide pin 22 by hand. However, in some examples, the guidepin 22 can be rotated using an automated tool, such as a drill.

Once the tear 32 is resected, the cutter 24 can then be removed from theguide pin 22 (for example, using the tool 38). The guide pin 22 and thecutter 24 are then separately removed from the joint space 26. Byassembling and disassembling the cartilage trimmer 20 during surgery,the cartilage trimmer 20 is able to reach relatively narrow jointspaces. A “narrow” joint space is a joint space, or a portion of a jointspace, that is relatively small and perhaps difficult to visualize oraccess during surgery. Example narrow joint spaces include the lateraland medial compartments of a knee joint.

FIG. 3 is a cross-sectional view of the cartilage trimmer 20. In thisexample, the guide pin 22 includes an opening 40 on one side 42. Theopening 40 is provided adjacent, yet spaced-apart from, a distal end 44(the “distal” and “proximal” directions are labeled in the Figures) ofthe guide pin 22. The opening 40 includes a first connection portion 46configured to mate with a second connection portion 48 of the cutter 24.In this example, the first and second connection portions 46, 48 arethreaded and thus provide a threaded connection. Other types ofconnections are also within the scope of this disclosure.

The cutter 24 includes a blade 50 extending from the second connectionportion 48. The blade 50 includes a blunt distal edge 52 and a cuttingsurface 54 providing a sharp surface at a proximal edge 56. The cuttingsurface 54 is configured to resect cartilage. The cutting surface 54 canoptionally include a tooth 58 at a free end 59 of the blade 50 oppositethe second connection portion 48.

Providing the blade 50 with a blunt distal edge 52 and a cutting surface54 only at the proximal edge 56 decreases the risk of damage to healthycartilage and increases the precision to resect damaged cartilage.Providing the blade 50 on only one side of the guide pin 22 alsoincreases precision, and further allows the cartilage trimmer 20 accessto relatively narrow joint spaces.

The blade 50 is configured to connect to the guide pin 22 and projectalong a blade axis 60, which is substantially normal to a longitudinalaxis 62 of the guide pin 22. In the example of FIG. 3, an angularposition of the blade 50 relative to the guide pin 22 is adjustable. Inparticular, the blade 50 can be inclined away from a normal to thelongitudinal axis 62 in both a direction D₁, which is generally in thedistal direction, and in a direction D₂, which is generally in theproximal direction. In one example, the blade 50 is adjustable away fromthe normal by about 20 to about 30 degrees in either of the directionsD₁ or D₂. In a further example, the blade 50 is adjustable away from thenormal by about 25 degrees in either of the directions D₁ or D₂. In afurther example, the blade 50 is adjustable away from the normal byabout 24 degrees in either of the directions D₁ or D₂. In a furtherexample, the blade 50 is adjustable away from the normal by about 23degrees in either of the directions D₁ or D₂. In a further example, theblade 50 is adjustable away from the normal by about 26 degrees ineither of the directions D₁ or D₂. In a further example, the blade 50 isadjustable away from the normal by about 27 degrees in either of thedirections D₁ or D₂. In order to facilitate the angular adjustment ofthe blade 50, the first connection portion 46 is provided by a bushing64 received in the opening 40. Details of the bushing 64 are illustratedin FIG. 4. In this example, the bushing 64 includes at least one tab 66projecting into a corresponding channel 68 in the opening 40. In theillustrated embodiment, two tabs 66 are provided on opposed sides of thebushing 64, and the opening 40 includes two channels 68 corresponding tothe tabs 66.

The bushing 64 is moveable relative to the opening 40, and the movementof the bushing 64 is restricted by the arrangement of the tab 66 and thechannel 68. Specifically, the bushing 64 is moveable in the directionsD₁ and D₂, until the tab 66 contacts either end 70 of the channel 68.The ends 70 of the channel could be provided with resilient members, forexample, configured to bias the blade 50 to a position where the bladeaxis 60 is normal to the longitudinal axis 62.

In an example, the angular position of the blade 50 is passivelyadjustable. As the cutter 24 resects cartilage, the angular position ofthe blade 50 is influenced by the position of the guide pin 22 relativeto the adjacent cartilage. Alternatively, the guide pin 22 couldincorporate a rod connected to the bushing 64 to allow for activeadjustment. By allowing an angular adjustment of the blade 50, the blade50 can be positioned at an optimal angle for resecting cartilage. Theblade 50 can further be maneuvered into relatively narrow joint spacesthat are not otherwise easily accessed.

While the first and second connection portions 46, 48 of FIGS. 3-4provide a threaded connection, other types of connections are alsowithin the scope of this disclosure. For example, FIG. 5 illustrates acartilage trimmer 20 having a slot-and-pin connection. In this example,the first connection portion 46 includes a retention pin 74 selectivelymoveable into the opening 40. A surgeon, for example, can selectivelymove the retention pin 74 relative to the remainder of the guide pin 22.

The second connection portion 48 of the cutter 24 includes a slot 75.The retention pin 74 is selectively moveable into the slot 75 to retainthe cutter 24 relative to the guide pin 22. The slot-and-pin connectioncould allow for the angular adjustment of the blade as generallydiscussed above. In that case, the second connection portion 48 couldinclude a bushing.

FIG. 6 is an exploded view of another embodiment of the disclosedcartilage trimmer 20. In this example, the first connection portion 46includes threads 76 provided about an exterior of the guide pin 22. Thesecond connection portion 48 is provided by a bushing 78 having internalthreads 80 and configured to be threadably engaged with the threads 76of the first connection portion 46. The threads 76, 80 may be handedsuch that they do not become unwound during normal use of the cartilagetrimmer 20.

In one example, the cartilage trimmer 20 can be rotated primarily in aclockwise direction from the perspective of the surgeon (i.e., whenviewed from a location proximal to the cartilage trimmer 20). Suchrotation may cause the threads 80 to rotate relative to the threads 76in a counter-clockwise direction. To prevent unintended unwinding, thethreads 76, 80 are handed such that the bushing 78 continues to tightento the guide pin 22 as the surgeon rotates the cartilage trimmer 20clockwise. In this example, the threads 76, 80 are right-handed threads.This disclosure is not limited to right-handed threads. For example, thethreads 76, 78 could be left-handed threads for counter-clockwiserotation of the cartilage trimmer 20.

In the embodiment of FIGS. 6-7, the second connection portion 48includes a socket 82 receiving the bushing 78. The blade 50 is rigidlyconnected to the socket 82 and is provided on one side of the guide pin22. The inner surface of the socket 82 has a contour corresponding to anouter contour of the bushing 78. Thus, the socket 82 and blade 50 aremoveable relative to the bushing 78 to adjust a cutting angle of theblade 50 relative to the guide pin 22.

With reference to FIG. 7, movement of the socket 82 relative to thebushing 78 is regulated in part by a plate 84 provided over the socket82. Movement is further limited by a plurality of channels 86 formed inthe socket 82. The channels 86 receive tabs 88 projecting from thebushing 78. The tabs 88 are sized to allow movement of the socket in thedirections D₁ and D₂. In this example, angular adjustments of the socket82 are passive. As the guide pin 22 moves proximally during resection,the socket 82 and the blade 50 tilt in the direction D₁.

FIG. 8 shows the assembled cutter 24 in cross-section. Further, in FIG.8, the blade 50 has been adjusted such that the blade axis 60 istransverse of a normal axis 89 and is inclined in the direction D₁relative to the normal axis 89. In this example, the right-hand tab 88is in contact with an end 90 of the channel 86. Thus, the blade 50 hasmoved off the normal to a limit. In this example, a resilient member 92is provided at the end 90 of the channel to bias the blade 50 toward thenormal 89. The resilient member 92 is not required in all examples.Alternatively or additionally, resilient members could be provided onthe plate 84.

FIGS. 1-8 illustrate cartilage trimmers that are configured to beassembled during surgery. This disclosure also extends to cartilagetrimmers with cutters that are selectively moveable relative to theguide pin and deployed via an opening adjacent an end of the guide pin.FIGS. 9 and 10 illustrate two such examples.

Referring to FIG. 9, the cartilage trimmer 20 includes a guide pin 22having an internal passageway 94 extending from a proximal end to anopening 96 adjacent a distal end 44. In this example, the opening 96 isprovided in a side 42 of the guide pin 22 and is spaced proximally fromthe distal end 44. The internal passageway 94 includes an angled wall 98adjacent the opening 96 to facilitate movement of the blade 50 betweenthe internal passageway 94 and the opening 96. The angled wall 98 isinclined at an acute angle 100 relative to the longitudinal axis 62 ofthe guide pin 22. While the angled wall 98 has a constant angle in thisexample, the angled wall 98 could be curved in other embodiments.Further, the angled wall 98 could include more than one wall segment.

The cutter 24 in this example includes a blade 50 connected to a distalend of a rod 102. The blade includes a blunt distal edge 52 and acutting surface 54 at a proximal edge 56 only. The rod 102 is made of asemi-rigid material and is selectively moveable within the internalpassageway 94 by a surgeon. Movement of the rod 102 translates tomovement of the blade 50 between a retracted position within theinternal passageway 94 and a deployed, or cutting, position projectingfrom the guide pin 22 via the opening 96.

The rod 102 is formed such that the blade axis 60 is biasedsubstantially normal to the longitudinal axis 62 when the blade 50projects through the opening 96. The material of the rod 102 allowsmovement of the blade 50 off of the normal in the directions D₁ and D₂.Further, the material of the rod 102 allows the blade 50 to project in adirection parallel to the internal passageway 94 when passing within theinternal passageway. Example materials for the rod 102 include, but arenot limited to, nitinol, PEEK, or a combination of PEEK and metal (e.g.,a PEEK rod with a metal blade).

FIG. 10 shows an example cartilage trimmer 20 with a fully cannulatedguide pin 22. In particular, the internal passageway 94 extends in adirection substantially parallel to the longitudinal axis 62 from aproximal end of the guide pin 22 to the distal end 44. The internalpassageway 94 in this example terminates at an opening 104 at the distalend 44.

The cutter 24 in this example includes a blade 50 connected to a rod 102by way of a hinge 106. In this example, the hinge 106 is provided by abend in the rod 102. The hinge 106 is configured to bias the blade 50such that the blade axis 60 is substantially normal to the longitudinalaxis 62 when the blade 50 is deployed through the opening 104. The blade50 in this example is moveable between a folded position (shown near thebottom of FIG. 10), in which the blade axis 60 is substantially parallelto the rod 102 and a cutting surface 54 is positioned adjacent the rod102, and a cutting position (shown near the top of FIG. 10)substantially normal to the rod 102.

As with previously discussed embodiments, the distal edge 52 of theblade 50 can be blunt, which prevents damage to adjacent soft tissue asthe blade 50 moves from the folded position to the cutting position.When the blade 50 is retracted back into the guide pin 22, the blade 50would not be folded. Instead, the blade 50 would be distal of the hinge106.

It should be understood that terms such as “proximal,” “distal,”“medial,” and “lateral” are used consistent with their art-acceptedmeanings, and are used for purposes of explanation only. Terms such as“longitudinal,” “axial,” and “radial,” are used above with reference tothe respective axis and are also used only for purposes of explanation,and should not be considered otherwise limiting. Terms such as“generally,” “substantially,” and “about” are not intended to beboundaryless terms, and should be interpreted consistent with the wayone skilled in the art would interpret those terms.

Although the different examples have the specific components shown inthe illustrations, embodiments of this disclosure are not limited tothose particular combinations. It is possible to use some of thecomponents or features from one of the examples in combination withfeatures or components from another one of the examples.

One of ordinary skill in this art would understand that theabove-described embodiments are exemplary and non-limiting. That is,modifications of this disclosure would come within the scope of theclaims. Accordingly, the following claims should be studied to determinetheir true scope and content.

The invention claimed is:
 1. A cartilage trimmer, comprising: a guidepin; and a cutter including a blade moveable between a retractedposition within the guide pin and a deployed position projecting fromthe guide pin, wherein the blade has a cutting surface only on aproximal edge of the blade, wherein the cutter further comprises a) arod moveable within the guide pin, and b) the blade at a distal end ofthe rod, wherein the guide pin includes an internal passageway and anopening adjacent a distal end thereof, the blade projecting through theopening when in the deployed position, wherein the blade is moveablebetween a folded position substantially parallel to the rod and acutting position substantially normal to the rod, wherein the rodincludes a hinge distal of the blade when the blade is in the foldedposition; and wherein the hinge biases the blade to the cuttingposition.
 2. The cartilage trimmer as recited in claim 1, wherein theopening is at a distal end of the guide pin.
 3. A method of using acartilage trimmer, comprising: moving a cutter distally within aninternal passageway of a guide pin, wherein the cutter comprises a rodand a blade connected to a distal end of the rod, wherein the blade hasa cutting surface only on a proximal edge of the blade, wherein duringthe moving step the blade is in a folded position and is substantiallyparallel to the rod, and wherein during the moving step a hinge of therod is distal of the blade; and deploying the blade from the foldedposition to a cutting position by passing the blade through an openingadjacent a distal end of the guide pin and under a bias of the hinge. 4.The method as recited in claim 3, further comprising: resectingcartilage with the blade.
 5. The method as recited in claim 4, whereinthe cartilage is articular cartilage.
 6. The method as recited in claim4, further comprising: adjusting an angle of the blade relative to theguide pin while resecting cartilage.